Fatal error when user profile contains a repeating date field with data

    Notice: Undefined index: attributes_start in theme_date_display_range() (line 253 of /var/www/sites/learning-tv.com/sites/all/modules/contrib/date/date.theme).
    Notice: Undefined index: attributes_end in theme_date_display_range() (line 254 of /var/www/sites/learning-tv.com/sites/all/modules/contrib/date/date.theme).
    Recoverable fatal error: Argument 1 passed to drupal_attributes() must be an array, null given, called in /var/www/sites/learning-tv.com/sites/all/modules/contrib/date/date.theme on line 258 and defined in drupal_attributes() (line 2262 of /var/www/sites/learning-tv.com/includes/common.inc).

I have added a date field to the user entity.

In users where the repeating date element are blank, no error occurs. In a user where this data has been filled in, the above error is provoked.

I can remove the error by changing lines 253 and 254 in date.theme to:

$attributes_start = (isset($vars['attributes_start']))? $vars['attributes_start'] : array();
$attributes_end = (isset($vars['attributes_end']))? $vars['attributes_end'] : array();

But a look at the $vars variable shows that these keys in fact do not exist. Instead there is an 'attributes' key, but it is empty in my particular instance.